[Windsong]

So, we're on our second weekend of clearing the allotment and we've come across quite a few ant nests under some plastic and under some ply wood that had been left on the plot. It may actually be one huge nest.

The nest under the plywood measures (on the surface) about 9'x4'. a few feet away there was another nest about 3'x2'. This morning we also noticed a lot of them around the base of the apple tree, which we finished clearing around yesterday (there were brambles and ivy at the base of the tree).

Should we be concerned? Should we do anything about it?

[Jay The Digger]

Ants themselves rarely do any damage to veggies, but they can be a nuisance.

If I find one, I tend to open it up and let the birds strip it bare.  I only ever use dust if I find them in the house.

I always seem to find nests when I dig up my potatoes.  It makes furtling barehanded a bit like the treestump scene in Flash Gordon 

[fatcat1955]

A possible reason they are around the apple tree is that they farm greenfly. They look after them to obtain the sugars from their excretions. Try a sticky trap band around the trunk.

[Windsong]

Ants themselves rarely do any damage to veggies, but they can be a nuisance.

If I find one, I tend to open it up and let the birds strip it bare. 

We did just that. We dug most of the eggs out too. Drowned the suckers. I felt kinda bad but it didn't take long to get over it lol.

A possible reason they are around the apple tree is that they farm greenfly. They look after them to obtain the sugars from their excretions. Try a sticky trap band around the trunk.

Ugh. I read that they farm aphids too. Hopefully we don't have too much of a problem with those. Is this the sort of thing I should get for the tree?

http://www.harrodhorticultural.com/HarrodSite/search/product/Pest+Control_Insect+and+Pest+traps+and+barriers/GPC-255.htm